The present invention relates generally to optical devices, and more particularly to phase error correction of optical devices.
The operation of certain optical devices, such as waveguides, is phase sensitive. Control of the phase during device fabrication is typically not sufficiently precise, and phase correction needs to be applied after device fabrication. There are various methods for inducing a temporary phase shift in an optical device using mechanisms which actively dissipate power; examples of these methods include thermo-optic induced phase shifts, electro-optic induced phase shifts, and plasma-dispersion induced phase shifts. What are needed are method and apparatus for permanently correcting the phase of a phase-sensitive optical device. Phase correction without active power dissipation is particularly advantageous.